Abstract: A method and apparatus for estimating a position of an access point (AP) includes (a) measuring a strength of a signal, transmitted by the AP, at three or more measurement points (MPs), (b) selecting an imaginary attenuation factor, (c) calculating a range between the AP and each of the MPs on the basis of the imaginary attenuation factor and a strength of a signal measured at the MP, (d) calculating an intersecting point of ranging circles in each of which a position of the MP is a center and the range between the MP and the AP is a radius, (e) calculating a best intersecting point from among a plurality of the intersecting points obtained by repeating the steps (c) and (d) while changing the imaginary attenuation factor, and (f) estimating the best intersecting point as the position of the AP.

Abstract: Disclosed herein is a biometric information measurement apparatus using a user terminal. The biometric information measurement apparatus includes a light-emitting control unit, a camera, an image analysis unit, and a biometric information measurement unit. The light-emitting control unit controls the output of an optical signal from at least one light emitting element which outputs the optical signal to a part of a body of a user. The camera is to be placed to face the part of the body, and configured to capture light generated in such a way that the optical signal passes through the part of the body or the optical signal is reflected off of the part of the body. The image analysis unit analyzes an image captured using the camera. The biometric information measurement unit measures biometric information about the user based on the results of the image analysis.

Abstract: Disclosed herein are a method for handover in vehicular communications and On-Board Equipment (OBE) using the same. In the method for handover in vehicular communications, OBE performs a handover from first Road-Side Equipment (RSE) to second RSE. The OBE receives beacon frames from the first RSE and the second RSE. The first average value of a received signal strength indication corresponding to the beacon frame received from the first RSE and the second average value of a received signal strength indication corresponding to the beacon frame received from the second RSE are calculated. The first cumulative gradient of the first average value and the second cumulative gradient of the second average value are calculated. The handover from the first RSE to the second RSE is performed based on the first average value, the second average value, the first gradient, and the second gradient.

Abstract: Provided are a system for channel sounding of broadband single carrier mobile communications and a method thereof. A channel sounding device is provided, which achieves precise modeling of a broadband mobile communication in a 5 GHz band. The channel sounding device can perform precise channel modeling by collecting broadband channel data of 20 MHz between a base station and a mobile station moving at maximum 150 km/h, using a sounding signal including a 802.15.3 preamble, a maximum length sequence (MLS) signal, and a single carrier frequency domain equalization (SC-FDE) symbol overcoming a limitation of signal distortion of an orthogonal frequency division multiplexing (OFDM) signal. The channel sounding device can simultaneously perform modeling of interference of an adjacent channel as well as a transmission channel.

Abstract: Provided are a channel equalization and carrier recovery method and a receiving apparatus thereof. In the method, a receiver of the high speed wireless communication system obtains an initial value of a channel equalization coefficient through non-causal channel estimation in a frequency domain during a preamble transmission section of a packet. High-order QAM signal correction for updating the channel equalization coefficient in a time domain is performed during a data transmission section of the packet. when a payload section starts in the data transmission section of the packet, channel equalization coefficient tracking is performed on the basis of frequency domain decision, and a hard decision of a correction value by the high-order QAM signal correction in the time domain is made to correct carrier phase errors, so that the channel equalization coefficient is updated.

Abstract: Disclosed herein are a multicasting system and method for a vehicular communication network. The multicasting system includes a plurality of roadside communication devices for communicating with a plurality of vehicular communication devices. Each of the roadside communication devices includes a communication unit for communicating with the plurality of vehicular communication devices and at least one neighboring roadside communication device, a beacon analysis unit for analyzing beacon frames when a slot allocation request is received from one of the vehicular communication devices, a determination unit for searching for a period in which a slot has not been allocated and determining whether a period for allocation of a slot to the vehicular communication device is present, and a slot allocation unit for allocating a slot period for multicasting of the vehicular communication device based on results of the determination of the determination unit.

Abstract: A modulation device uses two base signal axes including a cosine function and two base signal axes including a sine function to modulate bit information and generate a modulation symbol. Accordingly, the frequency efficiency characteristic is improved while maintaining a great power efficiency characteristic.

Abstract: Disclosed herein is a method of providing vehicle wireless communication. In the method, a vehicle receives hand-over-related link information, which includes slot request information about slots requested by a vehicle to a roadside wireless communication device for hand-over of the vehicle, from a central control server. A hand-over preparation message, which includes the hand-over-related link information, is send to a vehicle wireless communication device connected to the vehicle. It is determined that the vehicle completed preparation for performance of the hand-over when a response message to the hand-over preparation message is received from the vehicle wireless communication device. Slots are allocated in consideration of the hand-over-related link information. Beacon frames, which include slot allocation information about the allocated slots, are transmitted to the vehicle wireless communication device.

Abstract: Disclosed herein is a biometric information measurement apparatus using a user terminal. The biometric information measurement apparatus includes a light-emitting control unit, a camera, an image analysis unit, and a biometric information measurement unit. The light-emitting control unit controls the output of an optical signal from at least one light emitting element which outputs the optical signal to a part of a body of a user. The camera is to be placed to face the part of the body, and configured to capture light generated in such a way that the optical signal passes through the part of the body or the optical signal is reflected off of the part of the body. The image analysis unit analyzes an image captured using the camera. The biometric information measurement unit measures biometric information about the user based on the results of the image analysis.

Abstract: A method and apparatus for estimating a position of an access point (AP) in a Wi-Fi system is provided. The method includes measuring a strength of a signal, transmitted by the AP, at three or more measurement points (MPs), selecting an imaginary attenuation factor, calculating a range between the AP and each of the MPs on the basis of the imaginary attenuation factor and a strength of a signal measured at the MP, calculating an intersecting point of ranging circles in each of which a position of the MP is a center and the range between the MP and the AP is a radius, calculating a best intersecting point from among a plurality of the intersecting points obtained by repeating the calculating the range and the calculating the intersecting point of ranging circles while changing the imaginary attenuation factor, and estimating the best intersecting point as the position of the AP.

Abstract: A RTT measurement system includes first and second signal time measuring devices respectively connected to two wireless LAN devices and a RTT estimator. Each one of the first and second signal time measuring devices senses a transmitted signal from a corresponding WLAN device and a corresponding received signal and measures a signal time difference between the transmitted signal and the received signal. The RTT estimator estimates a RTT using the measured signal time differences at the first and second signal time measuring devices.

Abstract: A transmission apparatus selects a single transmission channel through which a transmission signal is to be transmitted from among unoccupied available channels, forms the transmission signal so as to alleviate interference with adjacent channels according to occupancy states of an upper adjacent channel and a lower adjacent channel adjacent to the transmission channel, and transmits the transmission signal.

Abstract: Provided are a system for channel sounding of broadband single carrier mobile communications and a method thereof. A channel sounding device is provided, which achieves precise modeling of a broadband mobile communication in a 5 GHz band. The channel sounding device can perform precise channel modeling by collecting broadband channel data of 20 MHz between a base station and a mobile station moving at maximum 150 km/h, using a sounding signal including a 802.15.3 preamble, a maximum length sequence (MLS) signal, and a single carrier frequency domain equalization (SC-FDE) symbol overcoming a limitation of signal distortion of an orthogonal frequency division multiplexing (OFDM) signal. The channel sounding device can simultaneously perform modeling of interference of an adjacent channel as well as a transmission channel.

Abstract: An apparatus for estimating a propagation delay time using signal transmission/reception receives an initial reception signal or a signal of which frequency offset is compensated to correspond to a predetermined condition and detects a peak time of a received signal. Next, the propagation delay time estimating apparatus estimates and compensates frequency offset of the signal of which the peak time is detected and redetects the peak time of the received signal of which the frequency offset is compensated to compensate the peak time of the received signal.

Abstract: Provided is an apparatus and method for estimating high-integration, high-speed and pipelined RLSs. Pipeline characteristics are given to an RLS algorithm to provide a high-speed HIP-RLS estimation apparatus. The HIP-RLS estimation apparatus has higher integration level than a conventional CORDIC-based RLS estimation apparatus. Thus, the use of the HIP-RLS estimation apparatus can reduce a chip size, thereby making it possible to fabricate more chips using the same wafer. Also, the HIP-RLS estimation apparatus is suitable for high-speed wireless communication because it has a high signal processing speed.

Abstract: A modulation device uses two base signal axes including a cosine function and two base signal axes including a sine function to modulate bit information and generate a modulation symbol. Accordingly, the frequency efficiency characteristic is improved while maintaining a great power efficiency characteristic.

Abstract: Provided is an apparatus and method for acquiring an initial coefficient of a DFE using an FFT.

Abstract: Provided are a channel equalization and carrier recovery method and a receiving apparatus thereof. In the method, a receiver of the high speed wireless communication system obtains an initial value of a channel equalization coefficient through non-causal channel estimation in a frequency domain during a preamble transmission section of a packet. High-order QAM signal correction for updating the channel equalization coefficient in a time domain is performed during a data transmission section of the packet. when a payload section starts in the data transmission section of the packet, channel equalization coefficient tracking is performed on the basis of frequency domain decision, and a hard decision of a correction value by the high-order QAM signal correction in the time domain is made to correct carrier phase errors, so that the channel equalization coefficient is updated.